1. Field of the Invention
The present invention relates to a chain guide having a guide shoe that guides a traveling chain by sliding against the traveling chain, and a plate that reinforces the guide shoe in a chain travel direction.
2. Description of the Related Art
A chain guide having a guide shoe that guides a chain traveling between sprockets by sliding against the chain is commonly used conventionally to stabilize the traveling chain and maintain an appropriate level of tension.
As shown in FIG. 19, for example, in a conventional timing system for an engine, in which a transmission chain CH such as a roller chain wound endlessly between sprockets S1, S2 provided respectively on a crankshaft and a cam shaft in an engine room E is caused to travel, the timing chain CH is wound endlessly between a drive sprocket S1 attached to the crankshaft in the engine room E and a pair of driven sprockets S2 attached to the cam shaft, and the timing chain CH is guided by a swinging chain guide (a swinging guide) 500 and a chain guide (a fixed guide) 600.
In this conventional timing system, the fixed guide 600 is fixed within the engine room E by two fixing attachment shafts Q, while the swinging guide 500 is attached within the engine room E to be capable of swinging about a swinging attachment shaft P in a winding plane of the timing chain CH.
A chain tensioner T maintains a tension of the timing chain CH at an appropriate level and suppresses vibration of the timing chain CH by pressing the swinging guide 500.
The chain guide (swinging guide) 500 and chain guide (fixed guide) 600 used in this conventional timing system are formed integrally from synthetic resin, and therefore, to secure sufficient rigidity and durability in the chain guides, respective guide main bodies thereof must be increased in size to realize improvements in the rigidity and durability. In so doing, however, it becomes difficult to achieve a compact design for the engine room E.
Therefore, in a conventional configuration (see Japanese Patent Application Publication No. 2006-2810, Japanese Patent Application Publication No. 2003-130156, Japanese Patent Application Publication No. 2002-266964, and so on), as shown in FIGS. 20 to 22, a chain guide 500 is provided with a guide shoe 510 that guides a traveling chain by sliding against the traveling chain and a plate 520 that reinforces the guide shoe 510 in a chain travel direction, a slit groove 512 serving as a plate housing portion into which the plate 520 can be inserted from below is provided on a rear surface side of a travel guiding portion 511 of the guide shoe 510, and the highly rigid and durable plate 520 is inserted into the slit groove 512 from below. With this configuration, strength, rigidity, and durability required of the chain guide 500 as a whole are secured while reducing an amount of space occupied thereby.